Colorectal cancer is the third most frequent type of cancer in the world, having an occurrence of about 1 million new cases every year. The incidents of cancer are considerably more frequent in the industrial part of the world.
Current techniques for mechanically performing anastomosis of hollow organs use circular mechanical staplers, which execute the connection of the tissue edges of the dissected hollow organ by metallic or plastic staples. A wide variety of surgical staplers have been developed for gastric, oesophageal and intestinal surgery. In performing surgical anastomotic stapling, generally two pieces of the hollow organ are joined by a ring of staples with a closed loopstapler. End to end anastomoses are generally performed by intraluminal surgical staplers that deliver a pair of staggered rings of staples. During this process, a circular knife blade is used to separate the tissue that is held within the circular ring. The separated tissue is then removed with the stapler to form a circular opening within the lumen along the stapling line.
A major issue regarding anastomosis healing is the blood circulation of the anastomosis during the healing process. Despite substantial development of surgical techniques during the last decades, morbidity and mortality after resections in the gastrointestinal tract, e.g. due to anastomotic leakage, remain as serious problems. Ischemia and inflammation, which are natural parts of the healing process, may cause leakage and secondary infection that may be fatal for the patient in the stapling area. Therefore, it has become common practice to relieve the pressure from the anastomosis by performing a deviating stoma, especially when the anastomosis is carried out in the lower part of colon and in rectum. By relieving pressure and faecal stream from the anastomosis during the healing process, the leakage incident may be reduced and fatal consequences of anastomotic dehiscence can be avoided. The inconvenience for the patient is obvious, since the patient must have a temporary stoma for a time period of about 3-6 months, and then has to undergo a second surgery in order to close the stoma. Unfortunately in many cases, the closure of the stoma cannot be reversed and the patient is forced to live with a permanent stoma leading to lower quality of life associated with increased costs. Another problem arising from stapling of anastomoses is anastomotic stenosis. The critical area for healing is the contact area between the two ends of the hollow structure to be connected. The connection has to be liquid proof, and the cross section of the lumen should be as wide and flexible as the original lumen. The size of the stapler determines the size of the lumen and thus the contact area between the ends. Surgical staplers create a smaller and more rigid opening compared to the cross section of the original lumen due to the staples inside the hollow structure connecting the two ends thereof, i.e. a collar may be formed that may lead to stenosis. For solving this problem repeated need for dilatation is required.
In this regard WO 2007/122223 discloses an anastomotic device for anastomosis of a tubular structure, such as an intestine, said device comprising members of a generally hollow open configuration. The device comprises a first member and a second member, wherein the first and second member each comprises a rigid part and an elastic part, respectively, and a connection member for connecting the first and second members to each other. This device improves the anastomosis by minimizing stenosis, while providing a self-discarding system.
WO 2007/122220 discloses a mounting tool for mounting such an anastomotic device to an end of an intestine. The mounting tool hereof comprises a receiving portion for receiving a rigid part of said device and a conical portion with a large end facing said rigid part having a diameter larger than or equal to the rigid part and a small end. The conical portion is insertable into the elastic part already arranged inside the tubular structure for expanding the diameter thereof and for passing the elastic part beyond the large end and onto a rigid part arrange able at the receiving portion.
However, when tumours are removed from lower part of the large intestine i.e. rectum, these parts of the intestinal system are inaccessible from the abdominal cavity. The pelvis minor is very narrow and funnel shaped, making it almost impossible to perform an anstomose from insert a hand from above. This fact severely hampers the possibility for working and suturing the area. In the last part of rectum, i.e. the bottom of the funnel and 5 to 10 cm from the sphincter, there is no possibility to reach from the abdominal cavity.
Hence, an improved mounting system would be advantageous and in particular a mounting system allowing for increased flexibility, cost-effectiveness, providing improved access to the lower part of the large intestine, rectum, and anal and/or improved control of the flexible part inside the intestine would be advantageous.